Substituted acrylates, polymerization

Table IL Substituted acrylates polymerized with ATRP...

Yuki, H. and Hatada, K. Sterospecific Polymerization of Alpha-Substituted Acrylic Acid Esters. Vol. 31, pp. 31, pp. 1—45. 

There have heen many studies on the polymerizability of a-substituted acrylic monomers.3jU35 33S It is established that the ceiling temperature for a-alkoxyacrylates decreases with the size of the alkoxy group. 35 However, it is of interest that polymerizations of a-(alkoxymethyl)acrylates (67)3 15 and a-(acyloxymethyl)acrylates (68)and captodative substituted monomers (69, 70) 39 appear to have much higher ceiling temperatures than the corresponding a-alkylacrylates methyl ethacrylate, MEA). For example, methyl a-... 

Polymerization reactions of suitably substituted acrylates can be initiated by radical generation through HAT [27]. It should be noted that hydrogen atom abstraction from the growing chain leads to interruption of chain growth. In such cases the organometallic complex possessing the pivotal M-H bond is reformed and... 

The bulkiness of the alkyl moiety on the heteroatom of the d substituent plays a very important role. a-Methylthioacrylonitrile polymerizes easily, but a-tert-butylthioacrylonitrile does not [67, 68], The same comparison holds for EtS- and tBuS-substituted acrylates [70]. 

A conventional explanation for the difficult radical polymerization of 1,1-disubstituted olefins is the known lowering action of bulky substituents on Tc. The classical example of this effect is a-methylstyrene [78]. Reported Tc values for substituted acrylates are collected in Table 9. Unfortunately, no Tc values have ever been reported for any captodative olefins. 

Table 15. Spontaneous polymerizations of captodative substituted acrylates CH2 = C(r/)COOR in bulk at 60 °C...

Synthetic methods targeting amino acid incorporation into functional materials vary widely. Free-radical polymerization of various amino acid substituted acrylates has produced many hydrocarbon-amino acid materials [161, 162]. In separate efforts, MorceUet and Endo have synthesized and meticulously characterized a library of polymers using this chain addition chemistry [163- 166]. Grubbs has shown ROMP to be successful in this motif, polymerizing amino add substituted norbornenes [167-168]. To remain within the scope of this review, the next section wiU focus only on ADMET polymerization as a method of amino add and peptide incorporation into polyethylene-based polymers. 

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